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5 link or H arms?
Posted: Wed Mar 16, 2011 10:05 am
by fredswain
I bought a JRX2 when they first came out. I remember I loved it. Over time I had problems with the rear springs hitting and binding in the trailing arm upper link so I also changed to the H arm setup when it first came out. That car evolved into a Pro-SE over the next few years and then I got out of RC. Fast forward about 18 years or so to today and I'm getting back into it again. I have yet to run that car again (RC10 and XX are getting back on the road ahead of it) but I got curious about the original setup. It has been so long since I drove that car and even longer since the multilink setup that I don't remember what each one drove like.
My question to those who have driven both setups (and remember it) or currently have both is from a handling standpoint which setup do you like better, the multilink or the H arm rears and why? Does one oversteer/understeer more? Does one seem to get better traction than the other? Clearly nothing is using that setup anymore and even the later versions of the car didn't have it anymore either. Tracks have changed since then as they used to be really loose dirt so I'd love to know how the original setup handles today and compares to a conventional rear suspension.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 10:12 am
by RCveteran
General consensus is 5 link is better for rough tracks which most today are not. I am competing (if you call it that) with a 5 link racer today on very smooth and prepped clay tracks just to be different and it works well. I am sure in the hands of a pro it might go faster with h-arms but I am not that good to know or care. At the local club level my laptimes are respectable and the 5 link never stops drawing attention.
http://www.rc10talk.com/viewtopic.php?f=27&t=19073&hilit=racer
Not sure if I ever updated that thread, but car is pretty well planted, only real changes have been #56 losi shock pistons, orange springs all around and 35wt shock oil all around. I don't get to the track enough to tune all that often but this set up is working pretty well. I have no traction issues, car turns in and rotates well with a bit of brake.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 10:47 am
by kaiser
i turn a faster lap with my 5link jrx2 on our modern smooth clay track then i do with my b4.

Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 11:00 am
by RCveteran
Not surprising, when I see my car running I am not sure anyone who did not know would know it is 20+ years old in spirit.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 11:13 am
by fredswain
I'd love to get ahold of the parts to rebuild the 5 link so I guess I'll have to keep my eyes open. Since I'm grown up with the ability to do things I couldn't as a kid, I kind of want to design and build my own car from scratch. I think a variation of the 5 link would be neat to incorporate. I don't want to design a new kit or world champion car. I just want to play around and have fun experimenting. Perhaps I should just get the 5 link back on the old car again to relearn how it feels.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 3:22 pm
by kaiser
RCveteran wrote:Not surprising, when I see my car running I am not sure anyone who did not know would know it is 20+ years old in spirit.
you're right. the young kids at the track refuse to believe that it's older then them, then they get mad when it smokes their bandit.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 4:08 pm
by RCveteran
My favorite quote from a kid who worked at the track when I went with this car the 1st time and he looked at the 5 link, he said "That thing will never turn". I am not even sure where that came from; I just smiled and said "don't be so sure" proceeded to pass him in the turns

Another "old" guy on the driver stand said pretty loudly, looks like it turns to me

Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 4:42 pm
by soniccj5
kaiser wrote:RCveteran wrote:Not surprising, when I see my car running I am not sure anyone who did not know would know it is 20+ years old in spirit.
you're right. the young kids at the track refuse to believe that it's older then them, then they get mad when it smokes their bandit.
Not Losi related, but I had a kid ask me what my Rc-10 was when I was at the track. I told him it was an RC-10, and he said "I thought that was the name of the company."
Kids today..
Back on topic:
I would love to run my JRX2 with the old 5 link, but mine breaks so easy. I heard the first run of the JRX2s had weaker parts. Maybe I should find one on the bay to run

Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 4:45 pm
by RCveteran
Well my five link is a but custom with a titanium upper trailing link and RPM lateral links but no issues with breakage.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 4:52 pm
by bearrickster
the 5 link wins for style but they always seem to sloppy to me. I prefer the H arm. on a real rough track the 5 link would work better but their isnt very many if any rough tracks.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 4:57 pm
by aconsola
bearrickster wrote:the 5 link wins for style but they always seem to sloppy to me. I prefer the H arm. on a real rough track the 5 link would work better but their isnt very many if any rough tracks.
Even when built with all new parts, they have a lot of wiggle and jiggle to them. I have found the 5-link to be rather durable on the track if you use a good condition lower shock mount.
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 5:04 pm
by aconsola
fredswain wrote:I bought a JRX2 when they first came out. I remember I loved it. Over time I had problems with the rear springs hitting and binding in the trailing arm upper link
They changed the upper arms so that one of the flanged edges was flat, this gave more clearance for the springs.
see here:
http://www.rc10talk.com/viewtopic.php?f=27&t=3171
Re: 5 link or H arms?
Posted: Wed Mar 16, 2011 6:12 pm
by fredswain
Thanks for that bit of info. If I can ever find a multilink rear anywhere I'll know which one to look for. Then again with them being so rare beggars can't be choosers! I can mold new arms if need be and then change them a bit to suit but I need originals to copy.
I think they were a bit sloppy not because of the fact that they were multilink but rather because of how they were done. The inner arms were only spaced by an e-clip and there was a bit of slop there. That rear end could be redesigned to be quite tight which would probably affect the handling a bit as well.
Re: 5 link or H arms?
Posted: Thu Mar 17, 2011 7:51 am
by tucker330
I always ran the H arms after they came out. At the time it was not based so much on performance, but maybe I just wanted it to be more like my Associated. The H arms did seem to give me a little more front end grip. Translation: The rear didn't work as well so it was loose which made the front seem hooked up. The H arms also let me switch out shocks with my other cars because the didn't require that saddle mount.
Re: 5 link or H arms?
Posted: Mon Mar 28, 2011 8:38 am
by sgirouard
bearrickster wrote:the 5 link wins for style but they always seem to sloppy to me. I prefer the H arm. on a real rough track the 5 link would work better but their isnt very many if any rough tracks.
Way back when I raced my JRX-2 with the 5 link and then switched to the H-arm and stayed with it. But recently wanted to make my JRX-2 as a vintage racer. I changed where the shocks are mounted, instead of on the links that run parallel to the chassis, I have them mounted on the links that run perpendicular. A lot of the slop in the 5 link is because of the parallel links rotate on their ball links when the suspension moves.
You can see pictures of it here.
http://www.rc10talk.com/viewtopic.php?f=27&t=19854&start=15